Acer Travelstar 4062LMi Sound Problems!

Hi all, the gf's laptop has an issue with the sound. Where as it sounds rather warbled and breaks up whilst playing. Thought it may have been a speaker issue at the beginning, but does the same whilst playing through headphones.

It has been upgraded from 512mb to 1gb, i thought it may have been a memory conflict.

So i removed one stick from the computer to see if it may have been the cause, but to no avail.

I've also downloaded and reinstalled the audio drivers which are realtek high definition ones from acers own website, to no avail again.

Whilst playing around with the performance settings on the control panel, from hardware acceleration to software acceleration and the same rate from best to good. That didn't help either .

So now i think it maybe something linked to how the cpu is working along, because if you let the computer settle down and play audio its a little smoother and less gargled.

Has anyone any ideas without doing a fresh install of windows?

The specs are 1.73ghz Pentium M740 533mhz fsb 2mb L2 cache with 1gb of ddr2.

Has anyone ideas, maybe its a actual problem with the onboard sound. Which would mean its not worth repairing cost wise.

Many thanks in advance.